Predetermined torque release wrench



July 1, 1952 R. E. GARWOOD 5 5 PREDETERMINED TORQUE RELEASE WRENCH Filed Jan. 18, 1951 I /n ven z or.

ROBERT E GA/QWOOD.

Patented July 1, 1952 PREDETERMINED TORQUE RELEASE WRE Robert E. Garwood, Los Angeles, Calif., assignor to George C. Jenkins, doing business as Skyway Precision Tool Company, Los Angeles, Calif.

Application January 18, 1951, Serial No. 206,654

Thi invention relates to mechanics tools and more especially to a T handle adjustable torque wrench.

An object or the invention is to provide novel improvements in an adjustable torque wrench having T handle features.

Another object of the invention is to provide an improved T handle torque wrench having adjustable torque features wherein the amount of efiective torque may be readily indicated and determined.

Another object of the invention is to provide a novel adjustable torque T handle wrench wherein the torque setting after being made is secured against shifting.

Other objects and advantages will appear and will be brought out more fully in the following specification, reference being had to the accompanying drawing.

In the drawing:

Figure 1 is a perspective view of an embodiment of the invention.

Figure 2 is a side view of the same, partly in section, the section being taken along the line 2-2 of Figure 1.

Figure 3 is a sectional view taken along the line 3-3 of Figure 2.

Figure 4 is a partial sectional view taken along the line 44 of Figure 2.

The numeral Ill indicates generally the adjustable torque wrench of the present invention and comprises a tubular body H and a pair of radially extendingv handle portions I2, body ll having a bore 13 and portions l2 each having a bore 14.

A shaft element i5 is rotatable in bore l3 and has a plurality of flat side faces I 6 and a ratchet tooth formation IT at its lower end. A socket wrench element l8 having a ratchet tooth formation [9 for engagement with ratchet teeth I! is rotatable in bore 13 and is urged upwardly by coiled spring 26 which seats on a threaded sleeve 2| secured in the lower threaded end portion 22 of bore l3. A ball 23' or equivalent thrust hearing element is provided at the upper end of bore l3 for shaft element I5. Socket element l8 has a socket for a wrench tool shank 24 of conventional type.

A piston 25 is positioned in each handle bore [4 and is urged against the fiat side faces l6 of shaft element [5 by a coiled spring 26, which is seated on a plug 21 which has a threaded engagement 28 in the end of a cap element 29 Which has a threaded engagement 36 with the end of its respective handle portion l2 of the wrench body.

1 Claim. 01. 81-52.4)

Plugs 21 each have a screw driver slot 32 and may be locked in any adjusted position by a set screw 33 extending radially in cap 29.

Each cap member 29 is formed with an annular shoulder 34 having a plurality of notches 35 and body II is formed with a pair of recesses 36 in each of which is positioned a lever member 31 having a pivot mounting 36 in the body of the tool. One end of each lever 31 has a spring seat 38 and the other end 39 of each lever is adapted to interfit in one of the notches 35 of the associated cap member 29. By this construction each lever 31 may have its end 39 retracted from the notches of the associated cap by downward movement of its inner end against the pressure of spring 38. When thus retracted lever 31 permits its associated cap member to be turned to thereby increase or decrease the pressure of the associated spring 26 against the adjacent piston 25 in engagement with the fiat side faces l6 of shaft element l5. Cap elements 29 are shown as having three notches 35 and identification marks such as Ill, l5 and 20 may be placed'adjacent the several notches to indicate the torque limit of the wrench when the respective notches are e gaged by the ends 39 of levers 31. g

The operation of the invention should be clear from the foregoing description. A specific torque limit, such as represented by the numeral l5 may be provided for the wrench by associating the notches bearing the indicia I5 with lever 31 and, upon the rotation of the wrench which turns the shaft 24, a torque represented by the numeral IE will be applied to the nut or other element being tightened. When the tightening resistance increases above the numerically designated torque 15 the body I l of the wrench will rotate and pistons 25 will be retracted against springs 26 and will not cause a turning movement of shaft element I5. Plugs 21 may be shifted to adjust the normal pressure of springs 26 to provide the torque indicated by the indicia associated with notches 35.

While in the foregoing there has been shown and described the preferred form of this invention, it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.

I claim:

In a predetermined torque release wrench, a tubular body of T-form, a wrench spindle within the bore of the leg of said body, a. socket element within the said bore below said spindle, cooper- 3 ative ratchet teeth on the adjacent ends of said socket element and the spindle, a coil spring within the said bore below said socket element urging the latter upward to maintain the ratchet teeth engaged, an annular element threaded into the lower end of the said bore to adjust the tension of said spring, the upper end .of said spindle being squared, a piston slidably mounted within each of the opposite arms of said body to be alternately abutted against the adjacent of the flat faces of the said squared end, a coil spring within each of the said arms and bearing against the outer end of the complemental of said pistons, a cap member threaded 0n the outer'end of each of the said arms to adjust the tensioning effort of the associated spring-on :the adjacent of said pistons, each of said arms having .an elongated recess formed in the same adjacent the inner ends thereof, a lever pivotedin each of the said recesses, each of the ca members "having spaced notches formed in the innerend edge thereof,- and a-coil spring within each of said recesses and cooperative with the respective of said levers, to maintain an end of the same selectively engaged in the said notches to retain said caps against displacement from their positions of adjustment.

ROBERT E. GARWOOD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,165,159 Dunner Dec. 21, 1915 1,519,800 .Rifllard Dec. 16, 1924 2,157,574 Siesel May 9, 1939 2,332,972 Johnson Oct. 26, 1943 2,378,956 Thormer June 26, 1945 2,503,499 Livermont Apr. 11, 1950 2,525,379 Smilansky Oct. 10, 1950 FOREIGN PATENTS Number 7 Country Date Italy Aug. '31, 1937 

